Year Percent 1990 5.284 1991 5.271 1992 5.444 1993 5.563 1994 5.585 1995 5.669 1996 5.785 1997 5.914 1998 6.022 1999 6.128 2000 6.217 2001 6.217 2002 6.314 2003 6.279 2004 6.275 2005 6.439 2006 6.636 2007 6.785 2008 7.624 2009 8.559 2010 8.305 2011 11.3 2012 13.2 2013 12 2014 12.54 2015 13.1 2016 13.42 2017 13.609 2018 13.798 2019 13.988 2020 14.177 2021 14.367 2022 14.556 2023 14.745 2024 14.935 2025 15.124 2026 15.314 2027 15.503 2028 15.692 2029 15.882 2030 16.071